A tire angle change motor steers a host vehicle according to a tire angle corresponding to the rotation angle of a steering wheel detected by a steering wheel angle sensor. A gear ratio calculating unit of a tire angle control unit changes the amount of steering corresponding to the rotation angle of the steering wheel required for the tire angle change motor to steer the host vehicle, depending on the amount of pushing of the steering wheel detected by the pushing amount sensor. Therefore, it is possible to improve the convenience of a driving operation for steering. A pushing direction reaction force motor changes a reaction force generated against the amount of pushing of the steering wheel by the driver, depending on the speed of the host vehicle detected by a vehicle speed sensor. Therefore, the reaction force makes it possible to prevent the host vehicle from being steered by an unintended operation of the driver in various traveling states of the vehicle.
